The present invention relates to a drive with an external rotor motor for a vehicle wheel. More particularly, the present invention relates to a drive with an external rotor motor for a vehicle wheel which includes an external rotor designed as a wheel support rotatably mounted on a running gear link (or truck link) and stator laminations nonrotatably mounted on the running gear link.
A drive for a vehicle wheel is described in European Patent Document No. EP 0 052 344 A2. In this drive, the wheel rim of a motor vehicle, already available, is designed as an external rotor. The rotor lamination is mounted nonrotatably on the running gear.
An external rotor motor for an electric vehicle is described in German Patent Document No. DE 41 11 627 A1. The external rotor is incorporated in the rim of the vehicle wheel and thus cannot serve as a wheel support. The axial mounting space of the external rotor is limited by the rim flanges which are mounted by bearings directly on the body of the rim. The rim flanges serve as wheel supports and form the motor shielding. The stator laminations of the external rotor motor are mounted by bearings in the external rotor.
European Patent Document No. EP 0 413 337 A1 discloses an electric-motor direct drive for rail vehicles, in which an electronically commutated housing-less electric motor is mounted axially next to a vehicle wheel to be driven. The electric motor is mounted by its external rotor without interposition of a drive, to the axle shaft of the vehicle wheel to be driven. The direct drive is relatively wide axially, so that the vehicle wheels to be driven require a correspondingly wide wheel housing. As a result, especially in low-floor rail vehicles, the passenger compartment is narrowed in the area of these wheel housings.
German Patent Document No. DE 35 38 513 C2 discloses a hub drive with an electric motor for rail vehicles, in which the wheel support mounted in a wheel guide link is formed by the stator housing part of the electric motor. The rotor shaft of the electric motor is rotatably mounted coaxially with respect to the single wheel and meshes externally axially via a planetary transmission with the single wheel. Because of its compactness, the known wheel hub drive requires only small wheel housings, so that in low-floor rail vehicles a continuous low car floor is possible. However, the wheel hub drive according to German Patent Document No. DE 35 38 513 C2 requires sealing means as well as regular oil changes because of its transmission.
In addition, European Patent Document No. EP 0 249 808 A1 discloses an electric drive for motor vehicles in which the external rotor is mounted on the stator. The external rotor is connected through a transmission with the vehicle wheel to be driven.
Another drive for vehicles is disclosed in German Patent Document No. DE 25 35 418 A1. This drive is an external rotor motor mounted in a common tubular supporting axle of a wheel pair. The stator rests on a rod that runs inside the tubular supporting axle. The external rotor is mounted on the stator. According to a preferred embodiment, the drive motor can be connected by a transmission with the supporting axle.